In the present competitive electronics marketplace, there are continuing consumer demands for higher frequency electronic components enclosed in smaller packaging. These requirements have lead to increased temperatures within electronic packages, requiring more cooling. Higher frequency electronic components also generate more disruptive electromagnetic interference (EMI) which, if not properly shielded, can interfere with other electronic equipment that make use of transmitted radio frequency (RF) signals.
EMI emissions typically escapes electronic packages through ventilation holes commonly used for cooling purposes. Consequently, electronic manufacturers often face a design trade-off between cooling the package and shielding for EMI. Printed circuit boards used in various types of electronic equipment are typically mounted within a housing structure. During operation of the electronic device, EMI emissions are generated within electronic components, including circuit boards, chips, and other components mounted on the circuit boards. The EMI emissions emanate from these, and must be substantially prevented from escaping outwardly through the housing structure.
It should be noted that EMI emissions generated by electronic components can include electromagnetic energy of wavelengths along various points of the spectrum such as RF interference. As used herein, the term electromagnetic interference (EMI) refers to interfering electromagnetic energy of any wavelength.